In-app purchases. Paying for that game, without paying for that game.

However, there’s actually some more, and one is proving to be quite addictive. It’s called Best Fiends and is a simple puzzle slider game. You basically just highlight the similar icons and progress through the game.

The most popular games played on mobile devices around the world are this type. People just love being able to solve them. As an example,Monument Valley 2 offers players the chance to work their way through 14 levels, and the developers won awards too.

These games are pretty simple, pretty straightforward and easy to play. However, like a lot of these beautiful and addictive time-wasting games, there’s a tiny catch.

Now, I speak as someone who has played the odd gaming machine in a pub. Back when I worked in a supermarket I used to head to the pub after work and me and a couple of mates tried the gamblers. As a geek (as I am) you start to recognise patterns in certain machines. That, though, was back in the days when mobiles weren’t as technically advanced as they are now. The gambling industry is now experiencing a phenomenal rise in popularity on mobile, with players like mFortune Casino, becoming market-leaders in the area. They’re regularly bringing out new mobile casino apps for players to enjoy, such as their latest Spin Kingdom app. It’s a hugely immersive slot game app that is packed full of goblins, unicorns and trolls.

Here though, my wife has an app which isn’t a gambling app. However, it’s employing similar techniques in order for the app developers to get paid.

To begin with, things seem pretty straightforward. It’s free, it has great user ratings and it can be downloaded and played by anyone over the age of three. However, after not-too-long you’ll find yourself completely unable to progress, stuck on a level where there’s just not enough of one particular jewel, “fiend” or whatever is needed to move on. You try again, but you get stuck again. It seems impossible, or infuriating. Are you playing it wrong? Are you perhaps not good enough? Well, there’s one way around it…

An in-app purchase.

This, then, is where the “freemium” name comes into play. It’s a free game, delivered for nothing, but somehow I find some “micro payments” suddenly appearing in the bank account. £3.99 here, £7.99 there, another £3.99.. It creeps up.

After a short while, you suddenly think that it all the money had been saved, maybe I could’ve bought my wife that iPhone X after all.

App stores have labelled “In app purchases” against listed games and apps now, so you know that they employ these tactics before you download. However, you’ll not be immune to the frustration when you’re seemingly unable to progress through – what appears to be – an easy and simple game. You’ll be annoyed with yourself. You’ll think you’re having a bad day, and £3.99 won’t seem like a great deal.

The thing is though, would you have paid £3.99 to download the game before you started playing? Probably not. This, then, is how developers are getting their cash, and how they’re surviving in the modern age.